Judge Rules That Institutions
Can Join in Nasdaq Lawsuit

The class of investors suing Nasdaq market makers over alleged price-rigging can include institutions like mutual funds, a federal judge ruled Monday.

In a closely watched lawsuit that received class certification last November, lawyers for investors claim that 35 of Nasdaq's market makers conspired to keep the "spread" -- the difference between the prices at which they bought and sold 1,659 Nasdaq stocks -- overly wide. That alleged price-rigging inflated the traders' profits, the lawsuit claims, by overcharging...